Question

In a poll conducted before a Massachusetts city's mayoral election, 134 of 420 randomly chosen likely voters indicated that they planned to vote for the Democratic candidate. Suppose that an article describing the poll says that the margin of error for the statistic is 0.045.
Required:
Use this information to find an interval estimate and interpret the confidence interval.

Answer 1

Using confidence interval concepts, it is found that the interval estimate is (0.274, 0.364), and it means that we are x% sure(considering the confidence level) that the proportion of all voters in the city that plan to vote for the Democratic candidate is between these two values.

What is a confidence interval?

It is given by the sample proportion plus/minus the margin of error, and a x% confidence interval means that we are x% sure the population proportion is in the interval.

134 of 420 randomly chosen likely voters indicated that they planned to vote for the Democratic candidate, hence:

p = 134/420 = 0.319

The margin of error for the statistic is 0.045, hence:

0.319 - 0.045 = 0.274

0.319 + 0.045 = 0.364

The interval estimate is (0.274, 0.364), and it means that we are x% sure(considering the confidence level) that the proportion of all voters in the city that plan to vote for the Democratic candidate is between these two values.

More can be learned about confidence interval concepts at brainly.com/question/25890103